Oh, yeah, that karma . . . when I was pregnant with #1 I rode in a friend's car who had a toddler. I was disgusted by the state of her car and remember thinking, even if your DC gets Cheerios and little toys all over the seat, can't you at least clean it up when you get home. Yeah right. After bringing a toddler home from running errands, changing diapers or supervising potty time, getting them the meal or snack they are due, bringing in severals bags of groceries and the dry cleaning, mom might manage to finally go pee, but she's not gonna be heading back out to the car with a dustbuster to get it cleaned out on a daily basis.
I think much of the issue depends solely on your DC's personality. My DD will play with one type of toy (say, her dollhouse) and clean it up when she is done. My DSs like to mix up all the toys and various household items in their playing. It's creative, which I hate to squelch, but also created a messy house. For example, today they had a "Webkinz Parade" - they made parade floats out of various thing with wheels (shoeboxes with K'nex wheels, Lego vehicles, a shoe with Lego wheels taped to it), lit the parade route with the Chistmas lights they retrieved from the attic while I was in the shower, set their animals all up and down the "parade route" (which stretched through our entire house), took their desks light out into the hall to provide extra illumination, hung paper decorations they made for the event, yadda yadda yadda, got the picture? It was cute, it was fun for them, but now my house is a diaster and they have refused to clean it up and it is bedtime and now my house is messy and yes, I do blame it on having kids in the house!
Sometimes I think I haven't reinforced the "one toy out at a time" that other parents seem to have trained their children in, but then I look at DD and think it is just how some kids are born, cause she is so very different from her brothers.